Is there a prevailing consensus on determinism vs. free will, and the implications of that debate for the status of moral prescriptions? I am reading a piece by Derek Parfit, for example, which addresses the topic so briefly that it makes me wonder if his (compatibilist) position is the only one breathing. Thank you! -philosophy fan

There is not a prevailing consensus on the questions of (1) whether free will is compatible with determinism and (2) whether humans have free will. However, I would estimate that close to 2/3 of professional philosophers are compatibilists about free will and determinism (they think determinism poses no threat to free will), with the other 1/3 roughly split between libertarians (who are incompatiblists who believe that we have free will, and hence that determinism is false) and hard incompatiblists or skeptics about free will (who are incompatiblists who believe that we do not have free will because determinism is true and/or indeterminism would not help secure free will). These estimates are based on a large-scale survey I conducted (along with Thomas Nadelhoffer) and on another large-scale survey conducted by David Chalmers and David Bourget (see here; lots of other interesting results too). These survey results may be slightly off for various reasons (e.g., for these estimates, I've removed the 10-15% who pick "other" when offered only the three categories mentioned above, and among philosophers whose research focuses on free will, there may be more incompatiblists).

Since compatibilists believe we have free will (though they need not, and I argue that there are threats to free will distinct from determinism that make "skeptical compatibilism" a live position), and libertarians believe we have free will (though they argue that compatibilist free will is not enough), it looks like about 85% of philosophers believe we have free will, which is almost as many as the 90-95% or so of non-philosophers who, in my surveys, say they believe humans have free will.

However, it may be that many non-philosophers associate free will with a non-physical mind (or soul) and with the power to make choices ungoverned by natural laws (I'm not sure how committed "the folk" actually are to these theoretical claims and am testing that by doing "experimental philosophy" surveys). If the folk understanding of free will does include such commitments, then most philosophers (and probably most psychologists and neuroscientists) would argue that we lack that sort of free will.

So, whether we have free will or not depends on how you define "free will" and it depends on metaphysical and scientific facts about the way humans and the world work. For a good introduction to these debates, you may want to look at Robert Kane's A Contemporary Introduction to Free Will. And you can look at some of the answers panelists have given here at AskPhilosophers to questions about freedom.

Just to add a little to Eddy's fine response, which neatly limns both what position is taken on free will by most philosophers and the general state of play of the debates around free will. I just want to comment briefly on the status of the debate on free will for moral prescriptions--which I take to mean the justifiability of ascriptions of praise, blame, etc. (however they are understood--and there is debate, especially, on how to understand the nature of blame: for a sophisticated, but accessible and very clear treatment of this topic, see T. M. Scanlon, Moral Dimensions: Permissibility, Meaning, Blame). Both compatibilists and incompatibilists agree that ascriptions of praise and blame are justified just in case agents are free, but they differ--as Eddy pointed out--with respect to how they define free will, which definitions reflect differing views on metaphysical and scientific views about the nature of human beings and of the world. Very roughly, incompatibilists believe that in order to be free, agents must have the capacity to originate their own free choices, or, in an alternative formulation, that a free choice is one that is such that an agent can either do or not make the choice (this capacity is known as the 'Principle of Alternative Possibilities', or PAP); compatibilists, by contrast, tend neither to think that freedom requires that agents be the sources of their choices, nor that they have the capacity for alternative possibilities. But these are not the only positions that one might take with respect to the justification of ascriptions of praise and blame. Certain utilitarians, for example, believe that ascriptions of praise and blame are meant simply to encourage certain types of behavior (praiseworthy behavior), and discourage other types of behavior (blameworthy behavior), and think that ascriptions of praise and blame can achieve this end regardless of whether human beings are free. (For a classic statement of this position, see Moritz Schlick, "When is a Man Responsible?," or J. J. C. Smart's paper, "Free Will, Praise and Blame," which is collected in the second edition of Gary Watson's excellent collection, Free Will.) Whereas the sort of position advocated by Schlick or Smart is agnostic on the question of whether agents have free will, in recent years, Derk Pereboom has developed a related position, 'hard incompatibilism', according to which, roughly, because agents do not have free will (understood in an incompatibilist sense, as the capacity for agents to be the sources of their choices or actions), therefore the only use that ascriptions of praise and blame can have is that of encouraging good behavior and discouraging bad behavior: essentially, then, on this view, moral practices become a matter of social control.

Now although most philosophers work their way into the problem of free will by considering whether freedom is compatible with determinism, there's an alternative route, adopted, for example, by T. M. Scanlon in his magisterial work, What We Owe to Each Other: one might begin by getting clear about the nature of morality, and moral obligation, or moral practices, and then and only then turning to the question of what sort of freedom is required to underwrite such practices. The virtue of such an approach, to my mind, is that it keeps very clearly in focus just why it is we care about freedom--because we're concerned about the viability of our moral practices--and then seeks to determine just what sort of conception is necessary for those practices to continue to function as they do. (Such an approach, to my mind, casts serious doubt on the sort of revisionary account of moral practices advocated by Pereboom and philosophers such as Smart and Schlick. But this is a vexed matter.)

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